Cosmetics are generally defined as substances used to enhance the appearance or odor of the human body. They are generally mixtures of chemical compounds, some being derived from natural sources and others being synthetic. In the U.S., the Food and Drug Administration (FDA), which regulates cosmetics, defines cosmetics as “intended to be applied to the human body for cleansing, beautifying, promoting attractiveness, or altering the appearance without affecting the body's structure or functions.”
There are many different types of cosmetic products, including, but not limited to, hair treatment products such as shampoos and conditioners, body and facial cleansers, skin moisturizing products such as body creams and body lotions, facial products such as eye creams, wrinkle reducing treatments and anti-aging products, make-up products, as well as various other products known in the field. Examples of hair treatment compositions include U.S. Pat. No. 6,139,851 to Omura et al.; U.S. Appl. Pub. Nos. 2013/0090279 to Hilvert et al. and 2012/0276210 to Dihora et al.; and EP 1778181 to Soulimani, each herein incorporated by reference in its entirety. Examples of skin care products include U.S. Pat. No. 6,126,950 to Bindra et al., U.S. Pat. No. 6,544,530 to Friedman et al., U.S. Pat. No. 6,368,639 to Farooqi, U.S. Pat. No. 7,105,173 to Rolling, U.S. Pat. No. 8,372,825 to Turkowitz; U.S. Appl. Pub. No. 2012/0238743 to Kim et al.; EP 1441686 to Dokka et al.; and WO 2010/086724 to Surianarayanan et al., WO 2011/147696 to Chodorowski-Kimmes et al., WO 2003/041636 to Dokka et al., each herein incorporated by reference in its entirety.
Many cosmetic compositions, such as cleansers and shampoo, contain detergents. Sodium lauryl sulfate, ammonium lauryl sulfate, sodium laureth sulfate, ammonium laureth sulfate, stearic acid, lauric acid, myristic acid, oleic acid and palmitic acid are a few of the common detergents or soaps found in cleansers. See, e.g., Antczak, Stephen, and Gina Antczak. Cosmetics Unmasked: Your Family Guide to Safe Cosmetics and Toiletries. London: Thorsons, 2001, herein incorporated by reference. Soaps can be made from vegetable oil or animal fats. Coconut oil, olive oil, safflower oil, jojoba oil and tallow, for example, are ingredients used in creating soap-based cleansers. These ingredients are mixed with an alkaline substance, usually sodium hydroxide, or lye, to create a salt. When mixed, in a process called saponification, two byproducts are generally created: glycerin and salt.
Emulsions are among the most common types of delivery systems used in cosmetic formulations. An emulsion is a dispersion of one liquid in a second, immiscible liquid. Typically, cosmetic emulsions include an oily phase comprising one or more hydrophobic, long-chain, organic molecules and an aqueous phase. One or more emulsifiers are typically present to maintain the emulsion in stable form over time.
Various oils can be used in the oily phase of cosmetic compositions in the form of emulsions. Natural oils can be vegetable oils that consist of aethereal salts of glycerin with a large number of organic acids such as stearic acid, oleic acid, and palmitic acid, forming stearin, olein, and palmitin, respectively. Stearin and palmitin are common solid oils and fats used in cosmetic compositions. Olein is a common liquid oil used in cosmetic compositions. Natural oils can function, for example, as excellent emollients that leave the hair and skin soft and smooth. Oils can also penetrate the skin and provide effective nourishing and revitalizing effects. Therefore, natural oils are used in a wide variety of cosmetic products, including personal care as well as makeup products.
A growing number of cosmetic products are directed towards rejuvenating the skin and removing undesirable signs of aging such as wrinkles. Conventional products often contain exfoliating acids as active ingredients. Such anti-aging active ingredients include, for example, a-hydroxy acids (e.g., lactic, glycolic, citric), b-hydroxy acids (e.g., salicylic, 5-n-octanoylsalicylic acids) and retinoids (retinoic acids; retinol). However, these anti-aging acids can be associated with consumer discomfort characterized by burning, stinging, itching or a sensation of tightness after application.
There is a continuing need for new cosmetic compositions that exhibit advantageous properties. Additionally, there remains a general need in the cosmetics industry for products that retard or counter aging effects on the skin without producing undesirable side effects.